


C.A.S. For Short

by superhoney



Category: Supernatural
Genre: Alternate Universe - Canon Divergence, Background Case, Blow Jobs, Established Relationship, Fluff and Smut, Hand Jobs, Illustrated, M/M, Referenced Panty Kink, Short Shorts, Undercover, dcsmolthings, post s13
Language: English
Status: Completed
Published: 2018-09-24
Updated: 2018-09-24
Packaged: 2019-07-16 06:58:40
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,379
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/16080881
Author URL: https://archiveofourown.org/users/superhoney/pseuds/superhoney
Summary: This case probably isn’t even a case, and Dean just wants to go back to the bunker and continue their Bond movie marathon, but then Cas walks into the room wearingthat outfitand yeah, Dean is suddenly on board with this whole thing.





	C.A.S. For Short

**Author's Note:**

> Thank you to zaphodsgirl and her husband for the inspiration, the rest of the group chat for the enthusiasm and support, and Aceriee for the gorgeous artwork, which I was mostly joking about but boy did you ever deliver. Dedicated to A_Diamond, who said “do it for meeee,” and I did.

“So get this,” Sam says.

Dean rolls his head to the side to look at his brother, grimacing. “Sam. Seriously?”

He and Cas are in the middle of a Bond marathon here, and they’re about to hit the Daniel Craig era. Sam had better have a pretty damn good reason for interrupting this critical stage of Cas’ pop culture education.

“Seriously.” Sam isn’t even looking at the screen, fixed on whatever he’s reading on his tablet. “Three staff members at a high school have come down with a mysterious illness over the past two days. They’ve all slipped into comas, and no one can wake them up. Doctors can’t find anything to explain it.”

“You do know we’re not really with the CDC, right?”

That earns him a serious glare. “Come on, Dean.”

“It could be our kind of thing,” Cas says, pausing the movie.

Stung, Dean pouts at him, pushing aside the thrill of joy he feels at Cas including himself in that statement. “It could be,” he concedes. “But it could also _not_ be.”

“Dean.” Cas’ voice is lowered, his eyes going soft as he looks at him across the distance between their two armchairs. “If you’re not feeling up to it--”

“I’m fine.” Dean waves aside his concern. It’s been almost two weeks since they expelled Michael from his body. Two weeks since he woke up to Cas’ arms around him, two weeks since their lips met in a no-holds barred declaration of the feelings they’d both been keeping buried for far too long. They’ve been taking it easy since then, and honestly, Dean has enjoyed the time off. 

“Cas and I can go, if you want to stay here,” Sam offers. “It’s only a few hours away.”

Dean sighs and reaches for the remote, shutting the TV off. “No way I’m letting the two of you go alone.” It’s not just the break from hunting that has kept Dean so content the past few weeks. It’s also the totally unexpected situation he and Cas have found themselves in, sharing a bed every night and passing their days in the Dean Cave or taking long drives in the Impala together. It’s their richly-deserved honeymoon period, and there’s no way Dean is letting Cas out of his sight, not now.

“Well, that’s settled then.” There’s a smirk on Sam’s face that says he’s manipulated the situation exactly the way he intended to. “I texted Jody to let her know we’ll be gone for a few days in case Jack decides he wants to come home.”

“Great.” Turning away from Sam, Dean reaches down and pulls Cas to his feet. “Sorry, Cas. We’re going to have to finish our marathon another time.”

Cas just shrugs. “I’ll get my badge.”

“Yeah, about that.” Both Dean and Cas turn at the sound of Sam’s voice. “I think we’re going to have to take a slightly different approach on this one.”

***

“This is ridiculous,” Dean mutters under his breath. “I don’t see why we couldn’t both be FBI, like usual.”

They’re standing in their motel room, waiting for Cas to come out of the bathroom where he’s changing into his get-up for the investigation. Dean pulls at the fabric of his own disguise and scowls. 

“Because, Dean.” Sam’s voice rings with the weariness of someone who has listened to Dean’s complaints several times already. “There are three of us, and it makes more sense to come at this from different angles. Two of the missing staff members are the gym teacher and the custodian. If anyone is going to have access to the places they might have encountered whatever did this to them, it’s their replacements.”

“Yeah, sure. But why am _I_ the one stuck in these shorts?”

Before Sam can answer, Cas chimes in. “I am also wearing shorts, Dean.”

Dean turns around at the sound of his voice, his mouth going suddenly dry. Cas is wearing the uniform of the school custodian, a fitted dark blue t-shirt clinging tightly to his broad shoulders and matching cargo shorts leaving a tantalizing expanse of his legs bare. 

“You are,” Dean agrees. He’s always had a bit of a uniform kink, but in the past, it’s been more of a firefighter, cop, or military thing. This, though. This might be even better.

Or maybe it’s not so much the uniform as it is the person wearing it. 

He’s blatantly staring, but so is Cas. Under his appreciative gaze, Dean stops pulling at the bright red shorts he’s wearing, straightening up to his full heights. He can feel Cas’ eyes lingering on the patch of skin between the hem of the shorts and his red-and-white socks, the air between them crackling with intensity. 

This plan is quite literally looking better and better by the minute. 

“Look.” Cas pulls a small tag out from the side of the shorts. “They have my name on them.”

Sure enough, spelled out in bold black type are the letters C.A.S. Dean leans closer to read the smaller print below them. “Custodial action shorts?”

This close, he has an excellent view of the way the thick fabric clings to the swell of Cas’ perfect ass. Dean swallows roughly and pulls back before he does something that would be entirely inappropriate with his brother standing right there.

“Guys.” Sam’s voice is clipped. “Can you stop ogling each other for one second and focus here?”

“Should have thought of that before you insisted on wearing the fed suit, Sammy.” Dean gives him a cheerful grin. “Or before you insisted on taking this case to start with.”

“Whatever.” Sam sighs. “So, here’s the plan. You both head to the school, play your parts. Keep an eye out for anything suspicious. Listen in on conversations-- the students will definitely be talking about this, and you might overhear something they wouldn’t be willing to admit to the authorities.”

“Wait.” Dean holds up a hand. “You mean I actually have to teach?”

Sam gives him a stern look. “You’ve done it before.”

“Yeah, but--” He can’t find a good reason to protest. _Sorry, I just really want to look at Cas in that outfit instead of looking for monsters_ probably isn’t going to go over very well. “That was a long time ago, okay?”

“Dean.” Cas lays a gentle hand on his shoulder. “You’ve faced down things that would make most humans cower and tremble in fear. Surely, high school gym class can’t be worse.”

“Says the guy who’s never been to high school,” Dean mutters. Sighing, he tugs at his shorts again. They really are obscenely short. “Alright, fine. Let’s do this.”

None of the other gym teachers know anything. Dean asks a few polite questions about their missing colleague, and they all express their concern and sympathy, but can’t come up with any reason someone would have a grudge against him. Dean spends the morning playing dodgeball with two classes of giggling freshmen, all of whom seem to be taking the loss of their usual gym teacher in stride.

He sees Cas once, ducking into the locker room between classes, a broom resting casually against his shoulder. Dean gazes at him, the way his shorts conceal his powerful thighs but show off the equally impressive muscles of his calves, the breadth of his shoulders underneath his blue t-shirt. Cas looks up under the weight of his gaze, his own eyes roaming over Dean’s body, the white shirt and red shorts revealing far more of his skin than he normally shows. There’s no chance to talk, but Cas’ appreciative looks speak clearly enough. 

At lunch, he finds his way to the staff lounge. There, the subject of the mysterious illness is all anyone can talk about. One of the science teachers insists it’s something in the room, casting suspicious looks at the mugs piled in the sink as though it’s all their fault. Another teacher thinks it’s just a bad case of the flu, and yet another claims it’s stress. 

All of Dean’s careful questions about sulfur, cold spots, and other supernatural phenomena are met with blank stares. 

_Nothing so far_ , he texts Sam. _Anything from the principal?_

_Turns out all three of the victims were at the school when they got sick_ , Sam sends back a minute later. _They all started shaking and coughing, then collapsed and never got up. Sounds witchy to me._

It definitely does. Dean shudders. God, he hates witches. But at least now he has a better idea of what to keep an eye out for. 

He has older students in the afternoon, so he makes up some excuse while they’re busy running basketball drills and heads into the boys’ locker room to do a thorough search. He finds a truly alarming number of dirty socks, notes from classes dating back three years, and a few condom wrappers-- at least they’re being safe-- but nothing to indicate witch activity. He should probably check the girls’ locker room as well, but that will have to wait until classes are done for the day. 

That time can’t come quick enough. The kids aren’t so bad, honestly. They’re surprisingly polite and Dean actually has a good time joking around with them, but he just wants to wrap this case up and head home. 

He breathes a sigh of relief when the last bell rings and the students slowly trickle out of the gym. He makes sure to give them plenty of time to clear the area before sticking his head cautiously into the girls’ locker room. His voice echoes off the walls, and no one responds, so he searches it as quickly as he can, finding nothing suspicious. 

Frustrated, he texts Sam, hoping he’s having better luck. He’s looking down at the screen as he leaves the room and doesn’t register that someone has come up in front of him until he runs right into a firm chest that feels more like a brick wall.

“Dean.”

He is never, ever going to get sick of hearing Cas say his name. There’s always been something about it, some intonation that makes it sound sweeter coming from his lips than any others, but over the past two weeks, as their relationship has shifted and deepened, it gives Dean an entirely new thrill. Between that and the uniform, Dean is suddenly aware of the quiet hallway they’re standing in, the lack of people nearby.

He licks his lips, and Cas’ eyes flick downward to track the movement. “Have you found anything?” Cas asks. To a casual observer, he might seem unaffected, but Dean has learned the way his eyes go dark, the way his shoulders fold back like he’s restraining himself from reaching out to touch. 

“Nothing,” Dean answers. 

“Me neither.”

They stare at each other a moment longer. “Sam said something about witches,” Dean finally continues. “I’ve been looking for hex bags.”

“A good plan.” Cas’ eyes drop to his mouth again. “The last custodian was found in the hallway just outside his supply closet. Maybe we should check there.”

For a wavelength of celestial intent who never spent time in a high school, let alone got any action in one, Cas has sure picked up on the game pretty quick. “Checking for hex bags?” Dean teases. “Is that what the kids are calling it these days?”

Cas tilts his head to the side, expression solemn except for the mischief in his eyes. “Do you really care what we call it?”

“God no,” Dean says swiftly.

And that’s how they end up pressed against each other in the janitor’s closet, the door barely pulled shut behind them before their lips are sealed together. Cas kisses him like he’s starved for it, and Dean responds with equal hunger. They haven’t spent so many hours apart since that first kiss two weeks ago, and they both seem committed to making up for lost time. 

The closet is cramped, barely enough room for both of them to stand between the shelves, and lit by one dim bulb flickering above them. Still, it’s enough light to see by, enough to illuminate the hint of collarbone peeking out from beneath Cas’ t-shirt. Dean lightly trails his lips across that spot and feels Cas tremble under the touch, his hands digging into Dean’s hips as he pulls him closer. 

“Can’t believe I thought these outfits were a bad idea,” Dean says, breathless. “Christ, Cas, you look so fucking hot.”

Cas throws his head back with a groan as Dean pushes aside the collar of his shirt, sucking a bruise into the juncture of his shoulder and neck. “Dean--”

Before Dean realizes it, he’s being spun around, pressed against the door with Cas behind him. He’s seen evidence of Cas’ strength before, his quickness, but never in a situation like this. They’ve been exploring each other with tenderness, taking their time getting accustomed to the new sexual aspect of their relationship. But Cas has always had a good read on him, and Dean lets out a moan as Cas’ hands tighten on his hips, feeling the insistent press of his erection against his backside. 

“These shorts are outrageous,” Cas informs him, his breath hot on the back of Dean’s neck. “You should wear them more often.”

Dean laughs, a sound that quickly dissolves into a groan as Cas grinds against him. He shifts backwards, desperate, as Cas’ hands untuck his shirt from the shorts, running lightly over his stomach as they do. “You’re always beautiful to me, Dean. But this outfit, I confess, has kept me distracted all day, even when I couldn’t see you.”

Whatever reply Dean might have made is choked off as Cas’ hands dip below the waist of his shorts, running over the bulge of his erection before teasing around the hem of the material. “Cas--”

“It was difficult being parted from you for so long.” Cas’ hands travel back and forth between the waist and hem of the shorts, brushing against Dean’s cock without ever applying pressure. “The second the last bell rang, I had to come find you.”

The thing is, Dean has always known he and Cas share a deep emotional connection. A more profound bond, or whatever. But this isn’t like the situation with Michael, where Cas was frantic with worry over him. Or like any of the other times they’ve been separated due to the storm of chaos and absurdity that dominates their lives. There’s no fear for each other’s safety or for the safety of the world at large. This is just Cas missing him. Wanting him. 

Wanting him a lot, judging by the way he keeps pushing his hips forward, pinning Dean against the door.

Suddenly, Dean is being spun around, Cas’ hands at his shoulders rather than on his lower body. He lets out a whine of protest that dies on his lips as he takes in Cas’ serious gaze. “You’re quiet,” Cas notes. “Is this-- is this alright?”

It’s a fair question, and Dean appreciates the fact that he paused to ask it. “Yeah, Cas.” His voice is shaky. He hasn’t been silent due to a lack of enthusiasm. Exactly the opposite, in fact. “It’s good. Really good.”

Cas searches his face for a moment, then nods, evidently satisfied. Dean reaches up and pulls him into a slow, deep kiss that leaves his head spinning, then turns back around, angling his body so his backside brushes against Cas’ front again. “Come on,” he urges. He wiggles his hips slightly and is rewarded by Cas’ groan.

Within seconds, Cas’ hands are dipping back inside Dean’s shorts, freeing his cock from the tight fabric. Dean exhales shakily and tips his head forward, bracing it against the cool metal of the door. 

“You like this?” Cas asks, mouth pressed directly beneath Dean’s ear. 

“Yeah,” Dean pants, eyes slipping shut. “God, yes.”

Cas’ hand is warm and sure as it moves over Dean’s cock. With the other, he gently pulls Dean’s arms above his head, giving him plenty of time to resist. When Dean makes no move to do so, his one hand closes over both Dean’s wrists, keeping them pinned above his head as his other hand continues to work at him. Dean lets out another helpless moan and gives himself over entirely to the sensation.

“We have to be careful not to make a mess of these,” Cas says, his own breathing unsteady. “I want to see you wear them again, Dean.”

“We can get new ones,” Dean promises. “A whole bunch of them.” Cas’ hand twists in a particularly clever move and he tenses, fighting not to lose control quite yet.

“Maybe even shorter.” Cas lets go of his wrists and trails his hand down Dean’s back, sliding it up the back of the shorts from behind. “Or in other colours.”

He squeezes Dean’s ass in an almost thoughtful manner. “But those ones, I want you to only wear at home.”

Dean squeezes his eyes shut, overwhelmed by the images those simple words summon. “Just you wait until I see what I have in a drawer back at the bunker.”

Cas goes suddenly still. Dean whines, bucking his hips forward, trying to get more friction, but Cas holds him steady. “What do you have in a drawer back at the bunker?”

He sounds so intense, so commanding, Dean almost laughs. “Let’s just say if you like the shorts, I think you’ll like those too.”

“I’ll like you in anything,” Cas says, finally moving his hand again. “Or nothing.”

Dean is close, so close. “Yeah?” he gasps out. “Tell me about it.”

“I never understood the appeal of various outfits, the emphasis humans place on fashion.” Cas moves his hand faster, lips pressed close to the skin of Dean’s neck. “Until I saw you in these.” With his free hand, he tugs lightly at the hem of the shorts. “They are almost as bright as your soul, and they call to me just as strongly, though in a far more physical manner.” He bites lightly at Dean’s ear and a shudder passes over Dean’s entire body. “And despite your protests, I know you enjoy wearing them. I want to see you happy like this, Dean. Not just today, but every day.”

“Cas--”

It’s only been two weeks since they started doing anything like this, and Cas can already play him like a fiddle. Dean is breathless, straining both into and away from Cas’ touch, ready to explode. Ever so lightly, Cas presses one finger right against Dean’s entrance, just the barest hint of pressure, and Dean goes taut, his vision whiting out. 

“Come for me,” Cas whispers, and with a long, low moan, Dean does. 

He turns in Cas’ arms and presses their lips together, the last waves of pleasure still coursing through his body. Groping around on the nearby shelf, he locates a roll of paper towel and passes it to Cas so he can wipe his hand clean. Cas opens his mouth to say something, but before he can, Dean sinks to his knees. 

Cas looks down at him, lips parted in surprise and chest rising and falling rapidly, straining against the tight material of his t-shirt. “Dean,” he says, his now-clean hand coming to rest on Dean’s head. “You--”

“Let me.” Dean leans forward and mouths at Cas’ cock through the stiff fabric of his shorts. “Please, Cas.”

“Who am I to deny you?” With his other hand, Cas peels the ridiculous sweatband off Dean’s head and tosses it carelessly aside. 

Dean doesn’t answer. His mouth is otherwise occupied. Cas’ cock is hot and heavy on his tongue, a taste and feel that are quickly becoming familiar to him. He loves doing this, loves the way it makes Cas go quiet and still, the way his hands tighten slightly in Dean’s hair, not pulling but gripping with just enough force to demonstrate his enjoyment. The first time Dean did this for him, Cas came so quickly he was embarrassed about it afterwards, but Dean was damn pleased with himself. Cas is gorgeous in his pleasure, and Dean loves to look up at his face while he does this, tracking every sigh and every bite of his lip. 

Cas is so hard, so close already. Dean traces his length with his tongue, pulling back to suck lightly on the tip, then swallowing him down again. Cas groans and Dean moves away, replacing his mouth with one hand, the other running teasingly up the back of Cas’ leg, skimming over the sensitive bend of his knee. “These shorts of yours are pretty damn great too, you know. Not as short as mine, maybe, but I still like them.”

“They’re very functional,” Cas gasps out. “I found the pockets useful.”

Dean laughs, pressing a kiss to Cas’ inner thigh right beneath the hem of the shorts. “Functional, right. They’re also hot as hell. You’ve got the legs of a runner, Cas, all toned and strong. And you keep them buried under those loose pants all the time. It’s a shame.”

Cas looks down at him, a lazy grin curling up one side of his mouth. “Maybe I should borrow your shorts, then, one day. Or whatever it is you have in a drawer back at the bunker.”

“Fuck,” Dean breathes. The thought of Cas all decked out in some of his nicer underwear-- yeah, that’s definitely something they’re going to have to try. 

He leans forward to take Cas’ cock in his mouth once more, hands resting on his hips. He takes him in as deep as he can, breathing carefully through his nose, and feels Cas’ grip on his hair shift as he fights for control. “Dean, please,” Cas says. His voice is wrecked, and Dean feels a thrill of satisfaction, knowing Cas is so undone by him. “I’m going to--”

Pulling back slightly, Dean wraps one hand around the base of Cas’ cock as he concentrates his efforts with lips and tongue at the head. He looks up to meet Cas’ eyes, and that’s when Cas groans out his name, spilling hot and thick into Dean’s waiting mouth. 

Dean strokes him gently through the aftershocks until Cas disentangles his hands from Dean’s hair and carefully nudges him aside. He pulls Dean to his feet and kisses him sweetly, clearly not at all bothered by the taste of himself still lingering on Dean’s lips. 

They take a few minutes to try to put themselves back into some semblance of order, buttoning shorts and adjusting shirts. Dean’s sweatband is lost somewhere under the shelves and he makes a cursory attempt to find it, not really caring if he does. As he’s reaching to the back of the shelf, his hand comes into contact with something soft, and he pulls out a familiar-looking cloth bag with a crude symbol inked on its surface.

“Fucking witches,” he mutters under his breath, holding it up for Cas’ inspection.

“We should tell Sam,” is his response.

Right. They take the hex bag with them, carefully wrapped in a cloth, and cautiously emerge into the hallway, which fortunately remains deserted. Dean pulls out his phone and winces at the number of missed calls from Sam. The last text he sent just reads _Cafeteria. Now._

“Crap.” He shows the message to Cas, whose eyes immediately go guilty. “Which way is the cafeteria?”

They make their way over as quickly as they can, but their haste is unnecessary. Sam is lounging at one of the long tables, elbows propped behind him and a sour look on his face as he waits. “We found a hex bag in the janitor’s closet,” Dean announces, cutting off whatever smart remark Sam is definitely about to make. “So we’re for sure dealing with a witch.”

“Yeah.” Sam leans forward and crosses his arms over his chest. “I know.”

Cas frowns at him. “Did you also find a hex bag?”

“Better. I found the witch.”

Dean’s hand instinctively flies to his waist, forgetting that he isn’t armed. Leaving aside the fact that he would never bring a gun into a school full of kids, there’s no way he could have concealed one in these shorts. “Did you--”

“We had a nice, long talk about not taking out our frustrations on our teachers using spells found in a book she bought for a dollar at a garage sale,” Sam continues. Now he just looks smug. “I texted Rowena, she gave me a simple spell to reverse the initial effects, and she’s going to keep an eye on our disgruntled student. Says she shows great promise, misguided as she is.”

Dean’s brain skips merrily past the part where Sam and Rowena apparently _text_ now, focusing on the matter at hand. “So you just let her go? She almost killed three people.”

“She wasn’t trying to kill them,” Sam replies. “And she’s just a kid. I don’t think she’ll be a problem.”

He pauses, eyes scanning over them. “Besides. If you wanted a say in how we handled this, you should have been here. Not--” he raises one eyebrow-- “checking for hex bags, was it?”

Dean feels himself flush, but Cas looks rather pleased with himself. Sam just sighs and gets to his feet, shaking his head. “I’m really glad you two decided to come along on this case. Always good to have back-up.”

He takes off in the direction of the parking lot with the stride of the righteously indignant, tempered by the satisfaction of another job done. “This is all your fault, really!” Dean calls after him. “You’re the one who made us wear these outfits in the first place.”

Sam doesn’t bother to dignify that with a response.

“Come on.” Cas slides his hand into Dean’s pocket, tugging him forward. “The sooner we get home, the sooner we can get out of these outfits.”

“I like these outfits,” Dean protests, allowing himself to be led away.

“I know.” Cas leans over and presses a kiss to his cheek, then pulls back to murmur into his ear. “And you see, these shorts lived up to their name. They did see some action, even if it wasn’t strictly custodial in nature.”


End file.
